Fishing lines include, for example, a fishing line for reels which is used after winding around a reel, a fishing line for lure, a fishing line for fly, a fishing line for torrent fishing, a fishing line for sweetfish fishing, a decoy line and a leader line.
The properties commonly required for all these fishing lines to have are that they are light-weight and have high cord strength, as well as durability to maintain such properties for an extended period of time.
The majority of the fishing lines called fishing guts are generally made from nylon monofilaments. Along with the development of fibers called high cord strength fibers having a strength at break of 20 g/d or above, fishing lines made from such high cord strength fibers have been increasingly used particularly in deep-sea fishing, boat fishing and the like. These fishing lines are braids of 8 strands, 16 strands, and the like which have been coated with optional resins, wherein the fibers used are mostly made from ultra high molecular weight polyethylene alone.
In leisure fishing which is rapidly becoming popular in recent years, high quality but low price fishing lines have been desired. This is a consequence of growing recognition of the following practical problems associated with the conventional fishing lines which have a braid structure of 8 strands, 16 strands, and the like and which are made solely from a high cord strength fiber widely used for such use (typically Dyneema, trademark, manufactured by Toyo Boseki Kabushiki Kaisha).
(1) Braids suffer from low productivity (production rate is low and end breakage of even a single filament in optional number of necessary spoolings causes a great loss, thus greatly affecting the production efficiency), and low processing cost is difficult to achieve, which makes the price of fishing lines higher. PA0 (2) Braids can be continuously manufactured only in the length permitted to be wound around a spool winder used for manufacturing braids, so that long fishing lines are difficult to make and only short fishing lines can be manufactured. PA0 (3) Due to the braid structure, the fibers are substantially bent to an extreme degree for braiding. High cord strength fibers not in a straight line cannot exhibit mechanical properties to the fullest, such as high strength at break, high knot strength, low elongation at break and the like; in other words, cord strength utilization ratio is low. Specifically, for some high quality fishing lines made from a high cord strength fiber having a low elongation at break, fibers bent in use cause drastic fall of quality. PA0 (4) For stabilization of shape and for superior feel during use, such as stiffness of a fishing line, to be achieved, the braiding angle needs to be increased (i.e., smaller braiding pitch), which ultimately causes low cord strength at break and high elongation at break, thus degrading mechanical properties. PA0 (5) The constituent fibers have poor dyeability and fishing lines made therefrom cannot have various colors. PA0 (6) The constituent fibers have poor adhesion. When a resin coating is applied, the resin tends to easily fall off to cause transfer of color when wound around a reel, thereby impairing appearance and staining fishing tackle and fisherman. In order to inhibit such release of the resin, an anchor effect of the resin is required, which is achieved by impregnating the voids between fibers with large amounts of resin and allowing the resin to solidify. As a result, the amount of the resin to be adhered cannot be decreased but increased to cause larger weight of the fishing line, which in turn makes the size of the fishing line bigger and strength at break per size number smaller, thus degrading the property of the fishing line. PA0 (7) The service life of the fishing line is short, since the high cord strength fiber which controls the mechanical property of the fishing line is directly scraped by guides and the like. PA0 (8) The degree of damage to the fishing line can be confirmed only by way of the damage to the high cord strength fiber itself which accompanies impairment of properties, and the damage tends to be found too late. In general, the means for estimating the service life of a fishing line is the observation of fussiness of the surface of the fishing line which is caused by abrasion damage to the surface. In the case of a braid structure, the breakage of or damage to the fiber itself which affects the cord strength at break of the fishing line corresponds to the assessment means. Therefore, when the breakage or damage is found, the cord strength at break has already decreased, and the degree of damage can be judged only after the cord strength at break has decreased.
It is therefore an object of the present invention to solve the above-noted problems and more effectively utilize the properties of the high cord strength fiber to be used for fishing lines, whereby to provide a fishing line having superior mechanical properties as compared to those of the conventional fishing lines, such as a high strength at break, a high knot strength and a low elongation at break, as well as a high abrasion resistance, a greater length, and superior productivity.